<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>Insert title here</title>
<style>.one{
font-family:宋体;
font-size:24px;
color:red;
}
.two{
font-family:宋体;
font-size:24px;
color:red;
}
.three{
font-family:宋体;
font-size:24px;
color:red;
}
</style>
</head>
<body>
<h2 class="one">应用了选择器one</h2>
<p>正文内容1</p>
<h2 class="two">应用了选择器two</h2>
<p>正文内容2</p>
<h2 class="three">应用了选择器three</h2>
<p>正文内容3</p>
</body>
</html>